Recently, there is a growing demand for services having different traffic features, for example, a variety of multimedia application services (e.g., Voice over Internet protocol (VoIP), real-time games, video on demand (VoD), and so forth). With the increase in the types of services and the diversity in the service level requirements of a user, a communication system has been currently operated by considering not only system capability but also quality of service (QoS) representing user satisfaction. Moreover, since available resources vary in a wireless communication system due to a time-variable environment and the mobility of a mobile station (MS), a policy for ensuring the QoS is necessary.
Today, many wireless communication techniques are being proposed to achieve a high-speed mobile communication. Among them, an orthogonal frequency division multiplexing (OFDM) scheme is accepted as one of the most promising next generation wireless communication techniques. The OFDM scheme is expected to be widely used as a future wireless communication technique, and is currently used as a standard in the Institute of Electrical and Electronics Engineers (IEEE) 802.16-based wireless metropolitan area network (WMAN) known as 3.5 Generation (3.5G) technology.
However, a currently available broadband wireless access (BWA) standard defines only an interoperation process of media access control (MAC) layer QoS and does not provide a network interoperation process for ensuring end-to-end QoS which is noticeable to the user. In other words, in an IEEE 802.16-based network in which a physical (PHY)/MAC layer is supported, only a DSx interoperation process between a base station (BS) and an MS is defined, wherein dynamic service addition (DSA) represents service generation, dynamic service deletion (DSD) represents service deletion, and dynamic service change (DSC) represents service change.
End-to-end QoS of an application layer has to be ensured to enhance service quality noticeable to the user. Therefore, when using a BWA system in which only the MAC layer QoS is defined, the interoperation process for QoS setup has to be defined among an MS, an access network, and a core network.
In particular, the current standard does not provide a method for operating a per-flow mode of service flows (SFS), each of which is assigned with a service flow identifier (SFID), and which are managed by an MS performing a reconnection such as a quick connection setup (QCS) or a hard handover (HHO) or a fast base station switching (FBSS). Therefore, when a wireless network is congested, a call (i.e., the connection) may be disconnected according to a result of a connection admission control (CAC). In addition, resources may be wasted due to ineffective management of wireless resources.